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<title>Entity Search, Find, and Explore - Documentation</title>
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    <h1>Entity Search, Find, and Explore - Documentation</h1>
    <p></p>
    <h2>Text Search</h2>
    <p>Enter a text pattern to look for. Finder will show a listing of entities with the text
       occurring in any literal property value or label. You may then continue to refine your search
       by filtering by type, property value, etc.</p>
    <h2>Entity URI (ID) Lookup</h2>
    <p>You can lookup an Entity URI using the autocomplete feature which performs lookups as you type.
       The OpenLink Finder recognizes some well-known namespace prefixes. For example: "dbpedia:"</p>
    <h2>Results Order &amp; Ranking</h2>
    <p>On some listings, results are sorted using a combination of text match score and entity-attribute-value
       link coefficients. Thus, a small indicator graphic (horizontal bars in leftmost column) is used to unveil
       metrics for both rankings per entity; the top bar indicates the text score while the bottom covers the entity
       ranking. Hovering on either will reveal the actual value.</p>
    <h3>Text Scores</h3>
    <p>These are proportional to the frequency of the search terms in the match and if many terms are present,
       the score weight is increased by a proximity factor.
    <h3>Entity Rank</h3>
    <p>Entity matches are ranked based on how frequently they are referenced by other entities. Rankings
       are increased as a function of the score of the referencing entity.</p>
    <a name="timeout"></a><h2>Timeouts</h2>
    <p>The Virtuoso 6.x engine includes a new "Anytime Query" feature that enables the optional use of a configurable
       response time threshold (timeout) when executing queries over large
       datasets. This feature protects against deliberate or inadvertent denial-of-service style resource-hogging
       that can arise from badly written or complex queries.
       When enabled, this feature lets you to set hard limit for resource usage per query associated with
       unauthenticated users. Queries execute until the response time limit threshold is reached, and, if partial
       results are available, they are returned with additional result set diagnostics flagging the partial nature
       of the result set. All query handling is partitioned thereby protecting against cross-client resource
       contention.</p>
       <p>This service currently enforces a 20 second hard time limit for queries. Each query is first run with a 2 second timeout -
       if only a partial result or no results are received, the user is prompted to retry with double the previous time limit until
       the hard limit is reached.</p>
    <h2>OpenSearch</h2>
    <p>You can add this service as a search engine plugin in OpenSearch capable browsers. You can do this in Firefox by using the pulldown
    next to the search text input in Facet search main page.</p>
    <h3>More Information</h3>
    <ul>
      <li><a href="http://www.opensearch.org">OpenSearch.org</a></li>
    </ul>
    <h2>Available datasets</h2>
    <p>
    The <a href="/void/Dataset">VoiD graph</a> contains information about <a href="/fct/images/lod-datasets_2009-03-27_colored.png">Linked Open Data Cloud</a> datasets hosted by this instance.
    </p>
    <h2>More Information</h2>
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      <li><a href="http://docs.openlinksw.com/virtuoso/">OpenLink Virtuoso Documentation Main Page</a></li>
      <li><a href="http://virtuoso.openlinksw.com/dataspace/dav/wiki/Main/VirtuosoFacetsWebService">Virtuoso Facets Web Service Documentation</a></li>
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